White matter microstructural alterations in patients with neuropathic pain after spinal cord injury: a diffusion tensor imaging study

Dong Dong; Koichi Hosomi; Nobuhiko Mori; Yoshi-Ichiro Kamijo; Yohei Furotani; Daisuke Yamagami; Yu-Ichiro Ohnishi; Yoshiyuki Watanabe; Takeshi Nakamura; Fumihiro Tajima; Haruhiko Kishima; Youichi Saitoh

doi:10.3389/fneur.2023.1241658

White matter microstructural alterations in patients with neuropathic pain after spinal cord injury: a diffusion tensor imaging study

Front Neurol. 2023 Aug 24:14:1241658. doi: 10.3389/fneur.2023.1241658. eCollection 2023.

Authors

Dong Dong^{1

2}, Koichi Hosomi¹, Nobuhiko Mori¹, Yoshi-Ichiro Kamijo^{3

4}, Yohei Furotani³, Daisuke Yamagami^{5

6}, Yu-Ichiro Ohnishi^{1

7}, Yoshiyuki Watanabe⁸, Takeshi Nakamura⁵, Fumihiro Tajima³, Haruhiko Kishima¹, Youichi Saitoh^{2

9}

Affiliations

¹ Department of Neurosurgery, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan.
² Department of Mechanical Science and Bioengineering, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka, Japan.
³ Department of Rehabilitation Medicine, Wakayama Medical University, Wakayama, Japan.
⁴ Department of Rehabilitation Medicine, Saitama Medical Center, Dokkyo Medical University, Mibu, Tochigi, Japan.
⁵ Department of Rehabilitation Medicine, Graduate School of Medicine, Yokohama City University, Yokohama, Kanagawa, Japan.
⁶ Department of Rehabilitation Medicine, Kanagawa Rehabilitation Hospital, Atsugi, Kanagawa, Japan.
⁷ Department of Neurosurgery, Osaka Gyoumeikan Hospital, Osaka, Japan.
⁸ Department of Radiology, Shiga University of Medical Science, Otsu, Shiga, Japan.
⁹ Tokuyukai Rehabilitation Clinic, Toyonaka, Osaka, Japan.

Abstract

Background: Through contrastive analysis, we aimed to identify the white matter brain regions that show microstructural changes in patients with neuropathic pain (NP) after spinal cord injury (SCI).

Methods: We categorized patients with SCI into NP (n = 30) and non-NP (n = 15) groups. We extracted diffusion tensor maps of fractional anisotropy (FA) and mean (MD), axial (AD), and radial (RD) diffusivity. A randomization-based method in tract-based spatial statistics was used to perform voxel-wise group comparisons among the FA, MD, AD, and RD for nonparametric permutation tests.

Results: Atlas-based analysis located significantly different regions (p < 0.05) in the appointed brain atlas. Compared to the non-NP group, the NP group showed higher FA in the posterior body and splenium of the corpus callosum and higher AD in the corpus callosum, internal capsule, corona radiata, posterior thalamic radiation, sagittal stratum, external capsule, cingulum, fornix/stria terminalis, superior longitudinal fasciculus, and uncinate fasciculus.

Conclusion: The results demonstrated that compared with the non-NP group, NP pathogenesis after SCI was potentially related to higher values in FA that are associated with microstructural changes in the posterior body and splenium of the corpus callosum, which could be regarded as central sensitization or network hyperexcitability.

Keywords: corpus callosum; diffusion tensor imaging; neuropathic pain; spinal cord injury; white matter microstructural alterations.